Study: Even Rats Have Regrets After Passing Up A Good Deal

Ah, buyer’s remorse, that sinking feeling like maybe you shouldn’t have paid for that thing you just got. Or maybe you got a raw deal or passed up something you really wanted to settle for something else. That old ghost isn’t confined to haunting humans, researchers say — rats, too, can feel regret after passing up what they really want in the interest of another, less ideal deal with a shorter wait for satisfaction.

Researchers set up an experiment to mimic the kind of situation humans regularly encounter — you go to your favorite restaurant, the one with the crab rangoon done just right or the endless mimosas, only to find that the wait time is ridiculously long, reports The Scientific American.

In that scenario, we humanfolk might give up on our preferred meal in the interest of time, only to spend our meal at the second choice place regretting that we didn’t get what we want.

So scientists made a little restaurant row for rats, in which the rodents could only move through in one direction, and trained them to learn by the sound of a tone how long they’d have to wait for their meal.

Rats who passed up long wait times at “restaurants” that featured their favorite foods tore through their snacks at the runner-up spot, a sign that scientists say mean they regretted that choice. They’d also glance back at the place they passed up, as if remembering how great the handmade gnocchi there could’ve been, if only they’d waited.

Along with those clues, researchers peered into rats’ brains using electronic recordings and found that during that task, the part of the brain that’s active in humans when we feel regret effectively let them “read the rat’s mind,” the lead author explained.

When they looked back at the restaurant they didn’t stop at, rats’ brains showed a representation of entering that place, and not just of the food they missed. Researchers say those findings show that the rats actually regretted their actions, instead of just being disappointed that they didn’t get to eat whatever the rat equivalent of fried chicken and waffles is.

“Regret is something we think of as very human and very cognitive,” the senior author of the study said, but “we’re seeing that the rats are much more cognitive than we thought.”